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<h1 class="title">粒子系统性能指南</h1>
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<p>
粒子系统的性能随它所保持的粒子数量而变化。在建立理想效果的原型之后，性能可以通过降低粒子数来提高。相反地，如果性能在可接受的范围内，您可以增加粒子的数量，直到达到那个点(这会改善效果)。</p>
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请注意，粒子数通常是由粒子系统估计的，在某些情况下，明确地提供关于需要多少粒子的提示将提高性能。你可以通过在发射器上设置maximumemitter来做到这一点，它通常对不连续发射粒子的发射器很有用。</p>
<p>和<a href="qml-qtquick-shadereffect.html">ShaderEffect</a>一样，粒子系统的性能很大程度上依赖于它所运行的图形硬件。但影响者是个例外。对于不包括影响器的系统，粒子的大部分性能成本将在GPU上。由于GPU在并行处理大量操作方面做得更好，当不使用影响器时，更多的粒子可以在60FPS下绘制。</p>
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影响器，特别是如果修改javascript中的粒子，可能会相对缓慢，并增加使用粒子的CPU成本。尽可能避免在大容量系统中使用它们。一些简单的情况下，影响器可以避免使用定时<a href="qml-qtquick-particles-particlegroup.html">粒子组</a>过渡而不是时间触发的影响器，或设置加速度由于重力在发射器的加速度属性而不是重力影响器。</p>
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